Avaliação da atividade esquistossomicida in vitro do extrato hidroalcoólico bruto e metabólitos secundários dos frutos da Arctium lappa L. (Asteraceae)

Abstract

Schistosomiasis caused by the Schistosoma parasite is a disease that affects about 240 million people around the world. Praziquantel is the chosen drug for the treatment of this parasitosis. It is imperative to search for new molecules and / or prototypes with potential schistosomicidal activity. This requirement is due to the tough performance of the parasite against this medicine. In this context, the research with natural products has been recognized as an alternative to discover new pharmacos for Schistosoma treatment. Arctium lappa L. (Asteraceae) stands out among vegetal plants of interest for the production of schistosomicidal substances. This is recognized for being able to biosynthesize lignoid, a kind of metabolite that has performed great schistosomicidal potential. This master thesis describes the phytochemical study of the hydroalcoholic extract from A. lappa L. fruit, as well the evaluation of the schistosomicidal activity evaluation in vitro, facing the adult worms of S. mansoni from the extract and from its majority metabolite. The phytochemical study of A. lappa L. resulted in the isolation of two dibenzyl butyrolactone lignan, a arctiin e arctigenin. The results obtained schistosomicidal evaluation showed that hydroalcoholic extract crude in concentration of 200 mg/mL showed significant antischistosomal activity in vitro and is capable of causing the death of the 100% of the parasites within 24 hours of incubation. The arctiin a major purified metabolite from the extract, was capable of killing by causing tegumentary lesions en 100% of the adult worms. The obtained results suggest that the schistosomicidal activity in vitro showed by the hydroalcoholic extract can be related to arctiin presence, supporting the potencial schistosomicidal in vitro of dibenzyl butyrolactone lignan, against the adult worms of S. mansoni.